Thermodynamics of multi-component mixtures offers a means for operating heat-transformation systems applied to refrigeration or heating service. Due to pressure/concentration/temperature relations of solutions, composed of a working agent and a solvent, the latent heat of vaporization and condensation of the working agent can be utilized for temperature transformation of heat-fluxes.
Reabsorption systems of presently available designs make use of the functional relationship between pressure and temperature while concentration within a loop varies to a minor extent only. Therefore, two separate fluid loops have to be installed in order to adjust heat and mass balances as the former have to be operated under different concentration levels according to their temperature levels. This results in a relatively high investment in machinery, controls and components.
An example of a known reabsorption system is shown in Handbuch der Kaeltetechnik, Bd. VII (Handbook of Refrigeration and Cryogenics, Vol. VII), by R. Planck, Springer-Verlag, Berlin, West Germany, 1959, pp. 16-18.
In addition to the above mentioned desorber, absorber, reabsorber and degasser, two solution recuperators are required, which is responsible for the poor performance and the rather restricted application of such plants.
Furthermore, the operation parameters are strictly coupled to each other, e.g. by specifying the extreme temperature levels the intermediate temperature and pressure levels are fixed.